Nozzle



Patented Mar. 25, 193@ WILLIAM C. UHRI, 3R., OF CLAYTON, MISSOURI,ASSIGNOR T0 CENTRAL ENGINEERING .AND SALES COMPANY, OF ST. LOUIS,MISSOURI, A CORPORATION OF MISSOURI NOZZLE Application filed April 18,1925. Serial No. 24,115.

My invention relates to discharge nozzles such as are adapted to be usedfor washing and drying articles by means of fluid streams underpressure. My invention also embodies the production of an especiallyefficient atomizecl dual stream of fluid from such a nozzle.

The objects of my invention are to provide an etcient nozzle adapted tocombine a relatively small amount of fluid under high pressure with alarger amount of the same or another fluid under atmospheric or otherlow pressure so as to increase the flow through the nozzle of the fluidunder the low pressure and to `atomize the same. I also desire toeliminate back pressure and to provide a nozzle which may be adjustedand changed to suit different conditions. Another object is to provide astream of atomized water havingl different degrees of density at dierentpoints inits cross section.

My invention consists broadly in the provision of a nozzle having anelongated eX- panding discharge tube and an inlet for a comparativelyrestricted stream of motive fluid under high pressure aligned with saidoriliceand in the provision of another larger inlet for fluid under lowpressure adapted to be delivered from said orifice by the action of thehigh pressure lfluid passing through the orice. The use of my nozzleresults in a novel method of producing anratomized stream which methodis also an inherent part of my invention.

In the accompanying drawing illustrating my invention- The ligure is avertical section through a preferred embodiment of the same.

In the drawing the body of the nozzle is indicated at 1 andthe same isprovided with an elongated discharge orifice 2 comprising a Venturitube. Opposite orifice 2 the body 1 has an opening, the inner end ofwhich is provided with a peripheral flange la. A bushing 5 is threadedinto the body opening and an inlet/1 of restricted diameter is threadedinto bushing 5 and terminates adjacent the beginnin of orifice 2. Theinlet 4 is aligned with ori ce 2 and is adjustable to and from thelatter. Packing p is compressed between flange `1a and the end ofbushing 5 and the joint thus formed is not disturbed by adjustment ofinlet 4. v

A body of fluid under high pressure is connected to inlet 4. Anotherinlet 6 admits the same or another fluid under low pressure to the bodyreceiving chamber C. lThe stream line shape of t-he chamber interiorpermits the fluid admitted at 6 to flow freely around inlet 4 and intothe inner end of the Venturi tube discharge orifice 2.

In admitting a substantial volume of water around the restrictedcylindrical air stream and in confining the joint stream for asubstantial distance, gradually enlarging the diameter of the jointstream, a substantial quantity of the outer portion of t-he water streamis in contact with the interior wall of the discharge tube and continuesto contact with the inner wall of the tube throughout the length of thelatter and without being directly subjected to the air stream. Thisquantity of Water serves as a lubricant and moving vehicle for an innerstream of air and water.

. This condition produces a discharged stream of water atomized to ahigh degree and having an inner section, with a relatively high degreeof velocity, surrounded by an annular section of less velocity. Theatomization and Velocity results largely because the inner stream passesthrough the discharge tube Without being subjected to frictional contactWith the tube nor to cross currents created by one or more streamsrapidly expanding at the inlet end of the discharge tube and refiectedfrom the inner wall of the tube.' Since the entire discharged atomizedstream is eX- panding in diameter its impact is distributed over asubstantial area and the impact force per square inch is much less thanthe impactforce of streams produced by nozzles previously used andsupplied with air and water Y under pressures higher than I use or bynozzles discharging ordinary streams of restricted diameter. These arenovel results which I believe have not been obtained by any nozzlepreviously used.

In various mixing nozzles which have been used heretofore, it has beenthe practice to provided by the users.

supplywater to the same under subst-antial pressures in order to securea proper operation of the nozzle. The higher the water pressure thegreater the proportion of water which would be discharged by the nozzle.

Attempts to operate such nozzles without substantial pressure on thewater have usually resulted in the air shooting through the nozzlewithout drawing sufficient water through the nozzle to render thedischarge stream effective. Usually no attempt is made to utilizenozzles of the type referred to unless water over -thirty pound pressurecan be supplied. The apparent reasonffor the necessity of having waterunder pressure is that the air pressure in the nozzle instead of drawingthe water through the nozzle would prevent the water from beingdischarged from the nozzle. With the substantial pressures on the watersupply it has been also customary to use high pressure on the airsupply, eighty and ninet pounds pressure per square inch being requentlyrecommended by the manufacturers and These high Water and air pressuresalways produce a back pressure on the hand and arm of the user.

With my nozzle, water or air may be Supplied under atmospheric pressureor pressure slightly above atmospheric pressure and plenty of water willbe drawn through the nozzle. Because of my arrangement, it is notnecessary to use such high air pressures and I find that sixty poundsper square inch provides a very efficient operation of my nozzle.

`With my nozzle operated under the conditions just described, there isno noticeable or objectionable back pressure on the hand or arm of theuser.

In the preferred form, the outer portion 7 of the discharge orilice isdetachably secured to the portion 8 and by means of this constructionvarious lengths and different degrees of flare of the discharge orilicemay be provided. It will be noted that the parting line between portions7 and 8 is at the narrowest point of the Venturi tube. Hence changingportion` 7 for a similar member having a greater, or smaller, degree ofdivergence will not produce an objectional angle in the wall of theorifice.

The combination of the two inlets and the Venturi tube orifice may beutilized in the creation of a vacuum for cleaning purposes. If an opentube be connected at 6, the passage of air under pressure through 4 and2 will tend to create a vacuum in the nozzle and in the tube sufficientto clean dust from upholstery, etc. Modern .automobile Washing apparatusincludes an air compressor for supplyin air and water for washingpurposes an air alone for drying purposes. By means of my device theIsame apparatus supplies a-va'c'uu'm system for cleaning the cushions,tops, and other non-washable parts of the car and eliminates thenecessity of an expensive separate vacuum system or the alternatenecessity of foregoing the benefit of vacuum cleaning apparatus.

While I have referred to the passage of air under pressure through inlet4 and water through inlet 6, in the nozzle, it is obvious that otherfluids may be utilized in the device. For example, water undersubstantial pressure could be supplied to inlet 4 to draw water throughinlet 6 and discharge throughy the orifice. A Water pump of relativelysmall capacity could thus produce a substantially greater discharge thanthat obtainable by a larger water pump through the ordinary nozzle whichalmost invariably has a convergent orifice so made in an attempt toproduce a more forceful stream. Oil and other liquids may be similarlyatomized for various purposes. y

Various other modifications in the details of my invention Will besuggested to those familiar with the art and I contemplate the exclusiveuse of such as fall within the scope of the following claims.

I claim:

1. In a device of the class described, a tube of' substantial lengthexpanding in internal diameter throughout its length from its innertoits outer end, means for directing a comparatively small diametercylindrical stream of motive fluid into said tube and spacedfrom theinner walls of said tube near its ent-rance, and means for admittingliquid to said tube and surrounding said stream of motive fluid.

'2. In a nozzle for delivering a stream of atomized liquid, a motivefluid conduit having a restricted cylinder outlet, an expandingldischarge tube axially aligned with said conduit and extending from apoint adjacent to `the discharge end of said inlet, the smallestdiameter of said tube substantially exceeding the diameter of saidconduit and the ratio between the length of said tube and its smallestdiameter being not less than eighteen to one, and an inlet fordelivering liquid to said tube.

3. In a portable nozzle adapted to be manually manipulated fordelivering a stream of atomized liquid and varying the direction of saidstream, a body chamber, a gradually expanding discharge tube ofsubstantial length leading from one side of said chamber and terminatingat the point of its greatest width, an inlet opening at the oppositeside of said chamber for supplying Water or the like to said chamber andtube, and a member forming a substantially smaller and restrictedseparated conduit through said chamber for a m0- tive fluid and havin aninlet at said lattermentioned side-of said chamber, said conduitterminating in a portion ofconstant cross section for a substantialdistance and aligned with said discharge tube and surrounded by andspaced radially from the wall forming the entrance to said tube andadapted to project a stream axially of said tube and spaced asubstantial distance from the sides thereof.

4. The method of obtaining an, atomized mixture which consists informing a cylindrical air jet of restricted diameter, utilizing theentraining force of this jet to increase the velocity of a mass ofliquid surrounding the jet and supplied thereto at a pressure lower thanthat of the air supplied for the jet, shaping the resulting mass of airand liquid into a stream the first diameter of which is substantiallylarger than that of the air jet whereby the liquid may form an envelopefor thel air jet, and controlling the diameter of the rep sulting streamso that it increases uniformly in the direction of flow, whereby mixingof the air and liquid may occur along the surface of contact of the two,the control being exercised over a length of the stream suiiicient topermit substantial atomization of at least a part of the liquid by theair, then freeing the stream from the control.

5. The method of producing a stream of atomized liquid which ischaracterized by forming a cylindrical air jet of restricted diameter,utilizing the entraining force of said jet to increase the Velocity ofthe inner portion of a mass of liquid, delivered and coniined aroundsaid jet, in a stream of substantially larger diameter than the diameterof said jet and .under initial pressure lower than the pressure on saidjet, and controlling the ioint stream for a substantial distance so thatits diameter increases gradually, and then discharging said stream fromcontrol.

6. The method of obtaining an atomized mixture which consists in forminga cylindrical air jet of restricted diameter utilizing the entrainingforce of this jet to increase the velocity of a mass of liquidsurrounding the jet, shaping the resulting mass of air and liquid into astream the rst diameter of which is substantially larger than that ofthe air jet whereby the liquid may form an envelope for the air jet, andcontrolling the diameter of the resulting stream so that it increasesuniformly in the direction of flow, whereby mixing of the air and liquidmay occur along the surface of contact of the two, the control beingexercised over a length of the stream sufficient to permit substantialatomization of at least a part of the liquid by the air, -then freeingthe stream from the control.

In testimony whereof I hereunto aiix my signature thisth day of April,1925.

. WILLIAM C. UHRI, JR.

